The fuel cell has been proposed as a clean, efficient and environmentally responsible power source for various applications. A plurality of fuel cells may be arranged to form a fuel cell stack capable of powering an electric vehicle. One example of the fuel cell is a Proton Exchange Membrane (PEM) fuel cell. In the PEM fuel cell, hydrogen is supplied as a fuel to an anode and oxygen is supplied as an oxidant to a cathode. A common technique for storing hydrogen is in a lightweight, high pressure vessel resistant to puncture.
The typical high pressure vessel includes a thermal pressure relief device (TPRD). The TPRD is in fluid communication with the interior of the vessel and is configured to vent the hydrogen in the vessel when actuated, for example, when at least one of a predetermined temperature and a predetermined internal pressure is attained. The predetermined temperature and internal pressure may be attained during an operation of the vessel.
The typical TPRD is “one way”, meaning that the device may only be operated once. Following such operation, the TPRD is destroyed and must be replaced. However, it is desirable to employ quality control testing and inspection to verify that the TPRD is operating properly. It is presently not possible to test a TPRD, reset the TPRD, and subsequently install the tested TPRD in a high pressure vessel.
Another known pressure relief device is disclosed in U.S. Pat. No. 5,788,212, hereby incorporated herein by reference in its entirety. The pressure relief device has a thermally actuated trigger mechanism that interferes with a movement of a valve closure element. The trigger mechanism is elongated and shortens when heated to a set temperature, eliminating the interference with the closure element and actuating the pressure relief device.
There is a continuing need for a TPRD which can be tested, reset and subsequently installed in a high pressure vessel for use with a fuel cell stack. Desirably, the TPRD may be manually reset following the testing, improve security of a high pressure vessel, and have a manufacturing cost that does not substantially exceed the cost of existing pressure relief devices.